LONDON Monarch Airlines collapsed yesterday, the biggest ever failure of a British airline, stranding tens of thousands of travellers overseas and prompting the country's biggest-ever peacetime repatriation effort.

Monarch cancelled about 300,000 future bookings and apologised to customers and staff as it became Britain's largest carrier to go into administration.

"I am so sorry that thousands now face a cancelled holiday or trip, possible delays getting home and huge inconvenience as a result of our failure," Monarch chief executive Andrew Swaffield told employees.

"I am truly sorry that it has ended like this."

Transport Secretary Chris Grayling said the company fell victim to a price war over flights to the Mediterranean and told customers not to come to airports.

"We are doing our best to make sure that those people who are stranded and can't get back otherwise will be able to do so," he told BBC television, adding that he expected many of Monarch's more than 2,000 staff to get jobs elsewhere.

The British government has asked the Civil Aviation Authority (CAA) to charter more than 30 aircraft to bring back to the UK about 110,000 Monarch customers currently overseas.

Tough competition has been pressuring European airlines and driving consolidation, with Air Berlin and Alitalia filing for insolvency this year and seeking new investors for parts of their businesses.

The collapse will be a headache for some of the world's largest leasing companies, which financed its current fleet of 36 mainly Airbus jets, and for Boeing Co, which has sold the airline 32 of its 737 MAX aircraft. None of the planes has yet been delivered.

Although relatively small compared with Europe's leading carriers, Monarch had been a regular in the global battle for market share between planemakers as it shifted its loyalties between Airbus and Boeing. Boeing secured Monarch's agreement to revert to using its jets in 2014, following a fierce contest against Airbus and Bombardier.- REUTERS